1. Field of the Invention
The invention relates to an electronic device and more particularly to a method for forming a gas barrier on the electronic device.
2. Description of the Related Art
Organic light emitting diodes (OLED) have advantages of self-lighting emittance, quick response and high display quality. Thus, OLEDs are one kind of organic electronic device that is widely applied in organic light emitting displays. However, OLEDs are easy permeated by water vapor and oxygen, so that the efficiency and lifespan thereof are reduced. Therefore, OLEDs need to be sealed.
For conventional organic light emitting displays, the OLEDs are packaged by metal or glass. For example, U.S. Pat. No. 6,998,776 discloses using a glass plate as a package covering and using a gastight melting material to seal the OLEDs, wherein laser or infrared rays pass through the glass plate to process the gastight melting material. However, this kind of packaging material is not suitable for flexible displays. In addition, U.S. Pat. No. 7,198,832 discloses using a multi-layer structure to form a gas barrier. A film is coated on OLEDs by deposition to form the gas barrier and package the organic light emitting diodes. However, this kind of package needs several steps for its coating process, such that the fabrication thereof is time-consuming and the cost of the multi-layer structure is high.
Moreover, because the packaging methods of the conventional organic light emitting displays are performed by directly forming the gas barriers on the OLEDs and the OLEDs can only withstand a process temperature of smaller than 80° C., the process temperature of the gas barrier is limited and the water vapor and oxygen gas anti-permeation ability can not be enhanced.
Therefore, a method for forming gas barriers of electronic devices is desired, which is not limited by the acceptable process temperature of the electronic devices and the properties of the gas barriers can be improved.